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71.
42份武夷名丛茶树资源生化成分多样性分析 总被引:2,自引:0,他引:2
对武夷山茶区42份武夷名丛茶树资源的主要生化成分进行了评价鉴定和遗传多样性分析。结果发现,武夷山茶树资源的生化成分存在丰富的多样性和变异,平均遗传多样性指数达到2.06%,平均变异系数达到22.01%。通过多变量的主成分分析,前3个主成分代表了茶树生化成分多样性的89.02%的信息。基于生化成分,把42份武夷名丛聚类划分为3个类群。3个类群除了咖啡碱含量差异不显著外,其他各生化成分均存在显著差异。第Ⅰ、Ⅱ类群大部分为适制乌龙茶的资源,第Ⅲ类群大部分为适制绿茶的资源。并从中筛选出一批生化成分特异的资源。 相似文献
72.
SCoT分子标记在植物研究中的应用进展 总被引:3,自引:0,他引:3
SCo T是一种新型的目的基因分子标记,该标记不仅能获得与性状联系紧密的目的基因,而且能对性状进行跟踪,已被广泛应用于多种植物的研究。本文概述了SCo T标记的原理、引物设计方法及特点,并从PCR反应体系建立与优化、种质资源遗传多样性与亲缘关系分析、种质鉴定与指纹图谱构建、基因差异表达与分子遗传连锁图谱构建等方面总结了SCo T标记的应用进展。同时,对其存在的问题进行了讨论,并展望了该标记的发展应用前景。 相似文献
73.
采用针刺叶片接种法、温室地面水层保湿方式,对146份普通菜豆种质资源进行抗普通细菌性疫病鉴定和评价,结果表明,该接种方法简便实用,保湿方式效果良好,鉴定结果准确;从146份普通菜豆种质中筛选出抗病种质(R)2份、中抗(MR)种质50份、感病(S)种质81份、高感种质(HS)13份。本研究表明针刺叶片接种、温室地面水层自然蒸发保持湿度可以作为大规模菜豆抗普通细菌性疫病鉴定的适宜方法。 相似文献
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75.
We report here that, during periodical surveys of insects inhabiting diverse habitats for the collection of entomopathogenic
fungi; a large number of isolates were recovered belonging to seven species, from various regions of Madhya Pradesh and Chhattisgarh
forest areas and agricultural fields. The most common entomopathogenic fungi such as Beauveria bassiana, Nomuraea rileyi, Paecilomyces farinosus and Paecilomyces fumosoroseus were found to infect various insect hosts species naturally viz. Hyblaea puera, Eutectona machaeralis, Diachrysia orichalcea, Spodoptera litura, and few new insect hosts of these fungal pathogens among Indian insect population were collected for the first time from
Central India, such as beetles of Agrilus species, hairy caterpillars of Lymantria species. The isolation, identification, maintenance and pathogenicity assay of these isolates was performed prior to deposition
in culture collection center. 相似文献
76.
77.
贵州喀斯特山区野生葡萄实生苗抗旱机理研究 总被引:2,自引:0,他引:2
以4份2生年喀斯特山区野生葡萄实生苗为试材,通过塑料大棚盆栽试验研究了自然干旱胁迫下野生葡萄幼苗的外观形态特性和生理指标变化规律,探讨其抗旱性及其抗旱机理.结果表明;(1)4份野生葡萄的抗旱性存在明显差异,以葛藟葡萄'小七孔-3'的抗旱性最强,毛葡萄'天河潭-2'的最差.(2)干旱胁迫期间,'小七孔-3'的1级旱害症状出现时间比'天河潭-2'晚12d,且旱害指数始终小于其他3份种质.(3)抗旱性强的野生葡萄叶片相对含水量、可溶性蛋白含量高于抗旱性差的株系,而其叶片水分饱和亏、细胞膜透性、丙二醛(MDA)含量变化则相反,且材料间差异随着干旱程度的增强而增加;(4)野生葡萄叶片相对含水量与其旱害指数间呈极显著负相关,而其水分饱和亏、相对电导率、丙二醛含量与旱害指数间呈极显著正相关;细胞膜脂过氧化产物丙二醛含量增加是导致葡萄旱害的首要因素.研究发现,在干旱胁迫下,抗旱性强的野生葡萄叶片膜系统稳定,水分散失较少,细胞电解质外渗较低,渗透调节物质可溶性蛋白含量增加,从而维持了正常的生理代谢活动. 相似文献
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79.
We tried to answer the question to what extent neurons in the tectum of the superior colliculus (SC) of the cat and in regions of the mesencephalic reticular formation (MRF) localized more ventrally are involved in the
control of movements of the limbs. The impulse activity of neurons of the above-mentioned structures was recorded in animals
performing targeted operated food-procuring movements by their forelimbs (pressing the pedal). As was found, neurons with
impulse reactions correlating with forelimb movements are rather numerous in the SC and adjacent MRF, and there are several
groups of neurons, whose impulse responses reached their maxima within different phases of the movements. These were neurons
with peaks of the discharge frequency coinciding with the target-reaching movement, with the moment of touching the pedal,
with pressing the pedal, and with the development of the muscle force counteracting the forced withdrawal of the limb toward
the initial position. Such specific patterns of the responses of different neurons of the SC and neighboring MRF are indicative
of a rather specific involvement of the above structures in the control of forelimb movements in cats.
Neirofiziologiya/Neurophysiology, Vol. 39, No. 3, pp. 245–254, May–June, 2007. 相似文献
80.
BACKGROUND AND AIMS: Members of Rubiaceae are generally characterized by an inferior ovary. However, Mitrasacmopsis is cited in the literature as having a semi-inferior to superior ovary. It has previously been hypothesized that the gynoecial development of Rubiaceae with semi-inferior to superior ovaries takes place in the same way as in Gaertnera, one of the most commonly cited rubiaceous genera with a superior ovary. To test this hypothesis, a floral ontogenetic study of Mitrasacmopsis was carried out with special attention paid to the gynoecial development. METHODS: Floral ontogeny and anatomy of Mitrasacmopsis were examined using scanning electron and light microscopy. KEY RESULTS: At an early developmental stage, a concavity becomes visible in the centre of the floral apex simultaneously with the perianth initiation. A ring primordium surrounding this concavity expands vertically forming the corolla tube (early sympetaly). Stamen primordia develop inside the corolla. From the bicarpellate gynoecium only two carpel tips are visible because the ovary is formed by a gynoecial hypanthium. In the basal part of each carpel, a placenta primordium is initiated. Two septa divide the ovary into two locules. In each locule, the placenta becomes mushroom shaped and distinctly stalked. Eventually, the inferior ovary of Mitrasacmopsis develops into a beaked capsule. Only very late in the fruiting stage, the continuously expanding ovary is raised above the insertion point of the persistent calyx, changing the ovary position of Mitrasacmopsis from basically inferior to secondarily semi-inferior. CONCLUSIONS: Mitrasacmopsis follows an epigynous pattern of floral development. However, the presence of a prominent beak in the fruiting stage gives the whole ovary a semi-inferior appearance. This kind of secondarily semi-inferior ovary is shown to be different from the secondarily superior ovary observed in Gaertnera. 相似文献